1. Field of the Invention
The present invention relates to a bulky nonwoven fabric, a product using the bulky nonwoven fabric, and a process for producing the bulky nonwoven fabric.
2. Brief Description of the Background Art
Since common spunbond nonwoven fabrics and thermal bond nonwoven fabrics are inexpensive, they are widely used as convenient and common nonwoven fabrics. However, since fibers in a nonwoven fabric are not arranged in the thickness direction due to a production process, the obtained nonwoven fabric is inferior in bulkiness, cushioning properties and pleasant feel. In order to solve these problems, the bulky nonwoven fabric of the invention utilizes a difference in shrinkage between fibers. Examples of known nonwoven fabrics utilizing the difference in shrinkage between fibers are disclosed in the following Patent Literatures.
Patent Literature 1 discloses a nonwoven fabric wherein a non-shrinkable fiber web and a shrinkable monocomponent fiber web are partly thermally press-bonded and then heat-shrunk to form regular convex parts.
Patent Literature 2 discloses a nonwoven fabric wherein a non-shrinkable fiber web and a shrinkable monocomponent fiber web are partly subjected to needle punch entanglement or high-pressure hydroentanglement and then heat-shrunk to form a large number of rib-like convex parts.
Patent Literature 3 discloses a nonwoven fabric wherein a non-shrinkable fiber layer and a shrinkable fiber layer are substantially partly thermally press-bonded and then heat-shrunk and thereby parts which are not thermally press-bonded are protruded to form a large number of convex parts.
Patent Literature 4 discloses a nonwoven fabric wherein a non-shrinkable fiber layer and a shrinkable fiber layer are partly thermally press-bonded and then heat-shrunk and thereby parts which are not thermally press-bonded form a large number of convex parts.